Omnidirectional low noise piezoelectric transducer

Abstract

A piezoelectric ceramic transducer assembly for broadband noise-measuring drophone. A longitudinally polarized lead zirconate-titanate cylinder provided with end caps is sealed by O-rings within a circumferentially polarized lead zirconate-titanate cylinder providing high sensitivity, smooth response, omnidirectionality, and stability with temperature and hydrostatic pressure variations.

What is claimed and desired to be secured by letters patent of the United States is: 
     
       1. An electroacoustic transducer which comprises, a circumferentially polarized piezoelectric cylinder,   a longitudinally polarized piezoelectric cylinder sealingly capped by two concentric imperforate diaphragms,   and isolation means sealingly mounting said longitudinally polarized cylinder and diaphragms concentrically within said circumferentially polarized cylinder,   said isolation means cooperating only radially between said diaphragms and the inner ends of said circumferentially polarized cylinder.   
     
     
       2. The electroacoustic transducer of claim 1 wherein, said diaphragms have a radius less than the inner radius of said circumferentially polarized cylinder and said isolation means are O-rings mounted on the rims of said diaphragms.